Is lower uF acceptable with higher quality cap?

[Rapideye]

I need to replace some shitty jackon 6.3v 1500uF 8mm x20.

you guessed it, its an old Abit.
An SH6 which i rekon would be fun to use for a smoothwall server, as well as giving me something to do on a sunday ie: recapping.

I found these in 8mm as there isnt much room for all the caps around the CPU and they are fairly cheap:

http://uk.farnell.com/jsp/Passive+Co...questid=267941

Do you rekon they would work?

Ive removed and cleaned the old caps over 1000uF, which were all those crap jackon 150uF.

Im in the uk so any ideas would be cool.

[stevo1210]

Re: Is lower uF acceptable with higher quality cap?

Panasonic FM are low-ESR caps which are needed for motherboards and they should be OK in place of the 1500uf 6.3V caps. I don't think you will experience any issues by using 1200uf caps, they are close enough to 1500uf.

[starfury1]

Re: Is lower uF acceptable with higher quality cap?

The capacitance value is nominal anyway
when you add the tolerance in to the equation they maybe more or less of it.
(think 20%+-)

Its always better to go up rather then down but considering the quality of the FM's you probably would get away with it provided you not going to drive the MB like a racing car, some cpu's may put more strain on the VRM too so this is something you might want to check

I know theres a few here who could recommend possibly a more suitable replacement cap that would fit the bill
they can tell you better then I if you can use them but at a guess I think you would be ok to use the FM@1200uf
(I have some 1200uf FM [and this is not to say all ] but they measure 1500 uf mine are not the "L" version thought)

8mm in higher values, in quality caps are hard to find...its possibly due to the fact its hard to make decent caps in that size...
most quality caps in larger values seem to always come in a bigger can
I think this is the way it is..you want real quality...its a bigger can

but hang on for a few more replies from those that would know the situation better in regard to the MB

[Badcappy]

Re: Is lower uF acceptable with higher quality cap?

He might be able to tel Jackcon about his problem and they might send him replacements, as some people have on this forum.

1000uf or 1200uf replacements should be okay.

[gdement]

Re: Is lower uF acceptable with higher quality cap?

I've used 1500uF Rubycon MBZ's on an ABit BX133, those caps are available in the 8mm diameter. I don't know what sources you would have in the UK though.

If there are any unused parallel capacitor pads, you can also add extra caps at those positions to make up for the lost capacitance. But like others have said, you probably don't have to keep all the original capacitance, especially if you aren't pushing the board to it's limit - just get as close as you can.

[starfury1]

Re: Is lower uF acceptable with higher quality cap?

I am thinking there is probably no spare positions with that value
(thought did cross my mind after I posted)

another possibility is samxon....check with "big pope" here

replacement series for Rubycon MBZ is MCZ (so I understand)
dont know if the have 8mm in that value thought.

I dont know weather mixing values in the VRM output is a good idea
(just cause of different charge rates) I don't design them so not sure
Guess you would get away with it but I'll leave that open...me I probably wouldn't but thats cause Id err on the side of caution.
(think some here do thought?)

anyway good luck with it.

Cheers

[kc8adu]

Re: Is lower uF acceptable with higher quality cap?

whatever you use esr is likely more inprtant than uf
use the same in all positions in vrm output though as a cap with much lower esr than the rest will get more ripple tthan the others and may fail early.

[Rapideye]

Re: Is lower uF acceptable with higher quality cap?

many thanks everyone.

Do you rekon it would be wise to use a higher voltage on this board too.

Ive just seen a 'Tualatin pin mod' for S370 adapter cards, i dont know if it would benefit at all but id like to try that out and overclock it a bit ( abit, haha)

Those Panasonics are the only 8mm i can find that are close enough to 1500uF and are at 6.3v.
Ive tried all the dealers in the 'where to buy thread'

10mm may work, but i think it may be tight around the CPU and 24pin.

http://www.kumagaya.or.jp/~touma/image10/sh6.jpg

Do you rekon i could get 10mm around that socket?

[gdement]

Re: Is lower uF acceptable with higher quality cap?

You probably won't be able to squeeze 10mm against each other unless you use long leads. But you could try using a larger capacitance 10mm and don't fill all the positions. Another problem with 10mm is that the distance between the pins isn't the same, so the cap won't go down snug.
If you do this then low-esr becomes more important since there's less parallelism. Mathematically I suppose you can use the same formula as you would use for parallel resistors.

Higher voltage isn't necessary, but it will give you a larger cap with lower esr at the same capacitance.

replacement series for Rubycon MBZ is MCZ (so I understand)

Isn't the MCZ a much shorter lifespan cap than the MBZ? I'd be surprised if it's intended as a replacement, but I don't really know one way or the other.

[starfury1]

Re: Is lower uF acceptable with higher quality cap?

Thanks KC8
knew the was some reason why I didn't like the idea of mixed values caps in the VRM.
you explained it and put it in the more applicable correct terms...

Those panasonics are low ESR so Id run with them

0.030 ohm @100KHz ripple 1560 mA (read the pdf for more)

Got to work a lot better then the crap that was there.....

cheers

BTW you can use larger value uf caps and fewer of them to get same or near same total capacitance (some say more is better)
but as KC8 pointed out make sure all are same value, type


On MBZ MCZ I could be wrong! ...that was my understanding so would have to check that one.

[bgavin]

Re: Is lower uF acceptable with higher quality cap?

MCZ is the premium replacement for MBZ, according to the data sheets.

I bought 25 MBZ from Topcat recently, for a peculiar Intel board recap project. I couldn't find MCZ in the required size and spec, so I went with MBZ instead. Samxon is GA is another premium model to use.

[starfury1]

Re: Is lower uF acceptable with higher quality cap?

Ok just to add some info on the Rubycon MCZ , MBZ series

Check out the website Here
(probably grab the pdf's for reference)

I should add it does not state "direct replacement" just that 4 series are obsolete for low impedance and now they have 6 series available
(although since the now obsolete MBZ series are used on MB's and what they say below...you could take it, it is the replacement)

now to life expectancy, well it doesn't actually say.....

Under Endurance its states the spec's they should be within @ 2000Hrs
(on the pdf for both of them, well think thats what they mean?, worse case)

where as on the on the ZL series pdf it states at the top of the pdf
"Load Life" 1000~5000 hrs (depending on cap of course)

so stuffed if I know, check the pdf's ?

It does state on the MCZ pdf (at the above link)

105C Utlra low ESR for PC mother board

check the Series Chart pdf at this site Here
(thanks to pcbonez for that link)

anyway thats what I have managed to find out...for sure from the web.

Chere all

[gonzo0815]

Re: Is lower uF acceptable with higher quality cap?

MCZ are IMHO the direct replacement for MBZ, which will be discontinued as far as i know.

Comparing the specs, there is no reason to use MBZ for new designs, as MCZ are in any respect equal or improved to the MBZ.

Edit: MCZ are availiable in 8mm diameter and 1500uF €6.3v.